Rail testing apparatus



March 1936- A. E. F. BILLSTEIN ,034,280

RAIL TESTING APPARATUS Filed July 2, 1932 2 Sheets-Sheet 1 WITNESSES: I N VEN TOR:

. 4A7'Hl/l? E. F B/LZSTE/A/ I BY M S Y W TTORNEYS.

March 17,- 1936. E, I T N 7 2,034,280

RAIL TESTING APPARATUS Filed July 2, 1932 2 Sheets- Sheet 2 WITNESSES.-' INVENTOR:

ATTORNEYS.

Patented Mar. 17, 1936"- PATE T OFFICE 2,034,280 'ms'rme APPARATUS Arthur E. F. Billstein, Altoona, 'Pa", assignor to The lennsylvania ltailroad Company, Philadelphia, Pa a. corporation of Pennsylvania 7 Application .I uly 2, 1932;Serlal No. 620,711

' 11 Claims. (Cl. 175-183 This invention relates to apparatus for test- Fig. It! shows a cross section of the detector ing railroad rails and the like for hidden cross-unit, taken as indicated by the arrows III-III sectional imperfections such as blow holes, fissures, etc. .More specifically, my invention has reference to testing apparatus of a type wherein; during travel 6f the apparatus over or along the rails, a flow of electric current is passed locally through each rail with creation of magnetic flux around it; and wherein a detector is affected by 10 variations occasioned in the flux. by imperfections in the rail, to influence, through the medium 'diiferent character, as well as between the iinperfections and the breaks or intervals between contiguous rail sections, so that the indications are more or less indistinct and therefore unreliable.

These deficiencies I aim to overcome in part through provision of a highly sensitive thermopile detector which responds readily and quickly 1 to the influence of flux changes to independent-' ly produce an electric current'of sufficient in# tensity for amplification to actuate the recording instrumeritalities, and which is of such slight thickness that it isnot'afiected by surface irregularities such 'as burns,- corrugations, etc.

A further aim of nminventionis to provide for the maintenance of the detector at all times at a predetermined fixed distance from the rail sur- 1 face similarly for immunity against affectation by low spotsor depressions formed at various points along the rails by wear of locomotive drive wheels.

I L Still/another object, of my invention is to provide means whereby a slight 'dehay is occasioned in an electric circuit through the recording in strument upon communication of -the'impulses through the amplifying means, from the detector,

to afford a slight though ample time period for said recording instrument to function and record prqpe 0f this invention wiil'be manifest from the detailed description hereinafter of the attached drawings, wherein Fig. I is a fragmentary side elevation of iny improved rail testing apparatus.

Fig. II is alon'gitudinal detail sectional view er the detecting unit .of the apparatus which-is directly Still other objects and attendant advantages fluenced by" variations in magnetic flux created locally in the rail.

. in Fig. II; and

Fig. IV is a diagram showing the wiring connections of the apparatus.

. As delineated in Fig. I of these illustrations; my improved 'rail testing apparatus comprises a car In with fore and aft supporting trucks whereof the wheels are indicated at H, l2 respectively, said wheels being of the usual flanged type to run on the rails 13 which are to be tested. Located intermediate the wheels I I, I2 at each side of the car. I8, is a smaller supplemental truck H with fore 'and aft flanged wheels l5, l6 which are smaller in diameter than the main truck wheels H, I2 butwhich, like the latter, run onthe rails 13. To opposite ends of the frame I! of the supplemental truck M are secured blocks l8, l9 'of,di-'electric material carrying multiple brushes 20, 2| to contact with the rails |3, said 20 brushes being connected in circuit with a low voltage generator G on the car l0, through conductors 22, 23. As the car I 0 travels along the -.rail l3 in the direction of the arrow,current obviously flows locally through the rail l3 in the interval between thebrushes 20, 2|, with atmental truck i4 carries a detector 25 which is supported, by means of a pair of fiat tongue springs 26, 21, centrally between the insulate blocks l8, l9. As shown, the springs 26, 21 exert downward pressure upon thedetector 25 so that 35 rounded bottomed shoes 28, 29, adjacent the lower corners of the casing 30 of said detector, are

maintained in light but firm contact with thetop surface of the rail i3. For a reason later on explained, the bottom curvature of the contact shoes 28, 29 is made to correspond with that of the treads of standard locomotive drive wheels.

In order that the supplemental-truck I4 may A be raised clearof therail' i3 incident to transport of the apparatus from one location of oper- 45 ations to another, I have provided a lifting tackle including a pair of cords or cables, 32 connected at 33, 34 ,to-opp osite ends of the truck frame I I which latter iscbnfined to vertical movement by guides 35 depending from the bodybf- 5o thecarlfl; I M r With reference now more especially to Figs. II

and III of the drawings, it will be observed that the casing 30 of the-detector 25 is in the form of a rectangular box constructed of a heat re- 55 '38, I1 constituting thermo-electric generators which'are adapted 'to be directly influenced by variations inthe flux 'around the rail ll. As

' 1 shown, each of these'detector units I, 81 conthermo-couples. These sists of aiflat oblong core 38 also molded from "crolite or other heat resistant di-electric material with ,oppositely inclined communlcatlnl grooves crosswise of its opposite sides 'whereinto are laid the components 30, I of serially arranged nents 30, ll may be respectively ofan allo'y of ermo-couple compo-- copper and iron and copper wire, or they be made of any other dissimilar metals suitable for the purpose; and, as shown in Fig. 111, they a tat s balance or equilibrium' of the circuit It to the amplifier II is disturbed, and the impulse thereby occasioned is immediately communicated to. the control relay It. By action of .this

the two secondary circuits ll, 80 are simultane-qs ousiy closed with the result that current is permitted to'ilow from the battery ll. through themagnet es of the recording instrument to indie I r cate the presence of the flow in the rail either on arecording chart or ribbon or on the rail itself. as may be found desirable in practice. Now since the actuation of the control relay I through-the i impulse received from the detector 2! is'in'stantaneous, the "control relay It would become'as quickly de-energized if it were not'for the time relay 5! 'which permits current from the battery Lto hold the switches operated by the relay." closed for a predeterminedtime interval and 'so are Joined at opposite corner edges of the core 1 permit t r device to function P vas ndlcated at; I, with the magnetically sensitive components all Lying in one plane, Also as shown in mg. 11, the thermo-pile' detectors 16,11 are placed of the casing II.

in longitudinally M relation with their W and bottom edges lodged recesses ll, 1e-

. spectively afl'orded' by said and its lid "a.

For the purprose of maintaining-the junctures ll, of the thermo-pile detectors at diiferent temperatures with maintenance of adifference of electrical potential between them, I employ ineachinstancaaheatingcoilll of covered wire which is lodged in a opening .46 through the crolite core a at one end, and

a coolingeoil 41 lodged in a similar vertical'open-r' ing at the other end of said core. As shown.,

the heating coil II is wound double to prevent the separate generator (not shown) on the car IO.

unitll mounted on the car ll.

packed with the detector as a: changed The cooling coil 41 of each detector unit is connected by pipes ll, II to a suitable To minimise flow of heat to the cold endof the core" and vice verse, I have perforated the central portion of the latter as at'II-in Pig. III. As a p ution against thermal on andradiation, the

casing II of the detector I" is suitable theme-insulating material such as; magnesium or the likeconventionally indicated at I8. I

As dically illustrated in Fig. IV of the drawings, the thermo-pile tmits SI, 81 of actuatingmagnetisindicatedatflJsconnected in; the secondary circuit'll.

magnetic duxdue to Thetionofthe 4 As incidenhto travel cfthecaril,current erly..v For ordinary PM the relay It may be set to function at 1/400 of a second. at the expiration of which'time it will serve to open the circuit through the battery II for de-energization of the control relay II. By its supporting springs 20,11, the detector re isyieldingly at" to correspond with the curvatlue'of the drive wheels of locomotives, the shoes, II ble .of accurately following the curvatures, of such convex depressions so that here again the spec- 'ing between the detecting units II, I! and rail surface is maintained perfectly 'As the dea result of the provisions just explained,

tector 25 is rendered capable .of 'tectingthe'imperfections in the rail as a consequence of its freedom from disturbance by the surface irregularities in the rail. Such of detection makes possible the accurate record-- ing of different 1 kinds of imperfections, or in; other words, the recordings will vary ln.accordv ance'withthe'sise and of the flawsin' 1 Having thus described my-in'vention. I claim:-'-

r-therailasthelatterisbeing V variations in the magnetic flux i. A detector for track rail testing apparatus 55 wherein a magnetic flux is produced locallyin I traversed, comprising a detector unltin the form of a thermo-elec- 4 tric generator adaptedto have its'voltage changed by variations in the magnetic?! flaws-in the rail. and-indicating means in circuit f2. s detector for an apparatus J wherein a magneticiilux is produced locally in the rail as the latter is traversed,-comprisinga de 'r unit inthe'form of a thermo electrie gen z rgaradaptedtohaveitsvoitage hangedfi I occasioned by flawsin't e sep tor b in 7 ofanumberofserially conn theraiLandindicatins'means incircui in" of as detector, for track restartin em wherein a muncti ilnx'is prodhoedlocallyin 2 uxoccasionedby ected verticallylag- 0 the rail as the latter is being traversed, comprising a pair of detector units in the form of thermoelectric generators spaced longitudinally of the rail and adapted to have their voltage changed by variation in the flux occasioned by flaws in the rail, said generators being opposingly connected so as to normally neutralize each other, and indicating means in circuit with the detector units.

4. A detector for track rail testing apparatus wherein a magnetic flux is produced locally in the rail as the latter is being traversed, comprising a detector unit in the form of a thermoelectric generator adapted to have its voltage changed by variation in the magnetic flux occasioned by flaws in the rail and composed of a number of serially-connected thermo-couples disposed transversely of the rail, means for maintaining alternate junctures between the dissimilar'cbmponents of the thermo-pile couples at difierent temperatures; and indicating means in circuit with said detector unit.

5. A detector for track rail testing apparatus wherein a magnetic flux is produced locally in the rail as the latter is being traversed, comprising a detector unit in the form of a thermo-elec- 'tric generator adapted to have its voltage changed by variations in the magnetic flux occasioned by flaws in the rail, said unit consisting of a flat vertical core of insulating material arranged transversely of the rail and wire segments of dissimilar metals respectively occupying grooves in the opposite sides of the core and joined at the opposite ends of the core, heating means within a hollow at one end-of the core and cooling means in a hollow at the other end of the core whereby the'alternate iunctures of the thermo-pile segments are'maintained at different temperatures, and indicating means in circuit with the detector unit.

"*6. A detector for track rail testing apparatus wherein a magnetic flux is produced locally in the rail as the latter is being traversed, comprising a di-electric casing, a detector unit in the 'form oi. a thermo-electric generator housed withto the curvature of locomotive drive wheels where by said detector unit is maintained at a constant distance from the rail surface irrespective of irregularities therein, and indicating means in circuit with said detector unit.

7. A detector for track rail testing apparatus wherein a magnetic flux is produced locally in the rail as the latter is being traversed, comprising a di-electric casing, a vertically-arranged detector unit within the casing influenced by variations in the magnetic flux occasioned by flaws in the rail, 9. shoe on the casing in line with the diet ctor unit and rounded to correspond with v s ace hollows formed in-the rail by wear of 10- comotive drive wheels whereby said unit is maintained at all times at a constant distance from the rail surface, means influential upon the casing to yieldingly maintain theshoe in contact with the rail, and indicating means; in circuit with the detector unit.

8, A detector for track rail testing apparatus by wear of locomotive drive wheels, whereby said units are maintained at all times at a constant distance from the rail surface, and indicating means in circuit with the generator units.

9. A detector for track rail testing apparatus wherein a magnetic flux is produced locally in the rail as the latter is being traversed, comprising a pair of detector units in the form of thermoelectric generators spaced longitudinally of the rail and adapted to have their voltage changed by variation in the flux occasioned by flaws in the rail, said generatorsbeing' opposingly connected so as to normally neutralize each other, a relay switch interposed in a primary circuit with the detector units, and a secondary circuit controlled by said switch having an indicating means interposed therein together with a switch governed by a time relay in another secondary circuit also controlled by the first mentioned switch.

10. A detector for track rail testing apparatus wherein a magnetic flux is produced locally in the rail as the latter is being traversed, comprising a casing, a vertically arranged thermo-electric detector coil within the casing composed of alternately arranged wire segments of diiferent metals and adapted to be influenced by variations in the magnetic flux occasioned by flaws in the rail, a friction shoe on. the casing having its center 'in the'axis of the detector coil and being rounded to correspond with the surface hollows formed in the rail by wear of locomotive drive wheels whereby said unit is maintained at all times at aconstant distance from the rail surface,

means influential upon the casing to yieldingly maintain the shoe in contact with the rail, and indicating means in circuit with the detector-unit.

1.1. A detector for track rail testing apparatus wherein a magnetic flux is produced locally in the rail as the latter is being traversed, comprising a casing, a; pair of vertically-arranged spaced thermo-electric detector'coil's within the casing composed of alternately-arranged wire segments 01' different metals and adapted to be influenced by variations in the magnetic flux occasioned by flaws in the rail, contact shoes on the casing respectively having their centers in, the axes of the coils and being rounded to correspond with the surface hollows formed in the. rail by wear of locomotive drive wheels whereby-said units are at all times maintained at'a constant distance from the rail surface means influential upon the casing to yieldinglymaintain the shoe in contact with the rail, and indicating means in circuit with the detector unit.

ARTHUR E. F. BIILSTEIN. Q. 

